The overall objective of this proposal is to develop an animal model system for study of lipoprotein synthesis and release which will yield information that will be applicable for future studies in lipoprotein synthesis and release in human liver slices and jepjunum. The specific goals of this research will be to complete the characterization on pig lipoprotein to develop specific radioimmunoassay to quantitate pig HDL, LDL and VLDL, and to define the factors which regulate the synthesis and release of pig plasma lipoproteins. Using the radioimmunoassays, the effect of cyclic nucleotides (cyclic AMP and GMP), hormones, ethanol, food substances and lipid-lowering drugs (clofibrate and nicotinic acid) on lipoprotein synthesis and release in the perfused pig liver and in pig liver slices will be studied. It is hoped that these experiments will provide new information and new insight into the mechanisms of regulation of lipoprotein synthesis and release which will be applicable to man.